Sure, sims like F4 and Flanker and Black Shark where there's a lot to learn about that plane.
However, there's not to much to learn about a SPAD or a Sopwith. You have an engine, stick, rudder, and MGs (maybe small dumb bombs). Flying and gunnery are the only things to learn, as in depth as they may be. You have to learn those same things to the same degree in Black Shark, plus you have things like the avionics, countermeasures, weapons that aren't guns, etc.
In short, the developers by necessity have to put a lot more effort into modeling just one plane if it's a post-50's model compared to post-WWII and earlier. So while I can accept a study sim of just an F-4 or any contemporary or later airplane, I find it hard to swallow when it's got no radar, no NAV, no radio, no missiles, no ECM, simple engines, not even retractable landing gear. What exactly are they putting all their time into?
Frankly, no home PC can truly model a damaged WWI bird with ripped fabric anyway, the equations are too complex and need to be approximated.